package com.xtwy.sign.ecc;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.ECPrivateKey;
import java.security.interfaces.ECPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import org.apache.commons.codec.binary.Hex;

public class ECDSATest {
	private static String src = "ecdsa security";

	public static void main(String[] args) {
		ECDSATest.jdkECDSA();
	}

	public static void jdkECDSA() {
		try {
			// 1.初始化密钥
			KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC");
			keyPairGenerator.initialize(112);
			KeyPair keyPair = keyPairGenerator.generateKeyPair();
			ECPublicKey ecPublicKey = (ECPublicKey) keyPair.getPublic();
			ECPrivateKey ecPrivateKey = (ECPrivateKey) keyPair.getPrivate();

			// 2.执行签名[私钥签名]
			PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(ecPrivateKey.getEncoded());

			KeyFactory keyFactory = KeyFactory.getInstance("EC");
			PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
			Signature signature = Signature.getInstance("SHA1withECDSA");
			signature.initSign(privateKey);
			signature.update(ECDSATest.src.getBytes());
			byte[] res = signature.sign();
			System.out.println("签名：" + Hex.encodeHexString(res));

			// 3.验证签名[公钥验签]
			X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(ecPublicKey.getEncoded());
			keyFactory = KeyFactory.getInstance("EC");
			PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
			signature = Signature.getInstance("SHA1withECDSA");
			signature.initVerify(publicKey);
			signature.update(ECDSATest.src.getBytes());
			boolean bool = signature.verify(res);
			System.out.println("验证：" + bool);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}
